handling errors through catch

So far I've bothered you all trying to eliminate the folloeing error

% set mum 20000000000
20000000000

set num_pnt [expr $mum-int($mum)]
integer value too large to represent

Since the value returned, wtitten in a point-info window, is correct I
wonder whether it would be simpler just suppress such an arror message.
To this purpose I was thinking of replacing the following
error-causing statement:
set num_pnt [expr $num-int($num)]
with
catch {set num_pnt [expr $num-int($num)]}

Is it going to fail or work ?

Thank you so much.

Maura

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